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Discussion Starter #1 (Edited)
OK, you're gonna get a kick out of this story. I don't want to tell it, but I might have really screwed up here. It's yet another story about the impatience of wanting to ride overtaking the knowledge that even the unexpected problems must be met with the right solution.

TL;DR: I crammed an air filter screen into the intake in a ball, and I want to know what the most likely outcome of this was, now that the screen is missing. Oh, the title of this should be "lost an air filter SCREEN", actually. Too late to change it now.

So, as some of you know, I struggled with getting my bike started for a couple of days in a row, and it turned out to be an AGM battery that went bad, after only a month (I got it replaced on warranty). That's a weird enough story, but hold on.

While assuming that it had to be anything else, other than the battery, I did a lot of things. One of those things was a carb backblow. The first step in that procedure sounds like it's saying to remove the air filter cases (ears) if you have them. I finally decided that it must really be about the carb vent tube, which comes out behind the right ear only, so I only removed the right ear.

But there's the rub: I removed the right ear completely. Meaning I took it off the rubber duct. And the rubber duct is a TIGHT fit to get back in, but of course, since it's really flexible, it's not the end of the world, once you know how to do it.

But here's the beginning of my problem: Once when I was taking off that right ear, I thought I needed to remove the bolts that secure the air filter, so I did (that's another reason to read up on these things before, instead of guessing). When I put those bolts back in, I must have done it wrong (too tight into the plastic or whatever), because now those bolts won't come out. And the fact that they won't come out prevents me from being able to remove the air filter from the air filter case.

I am assuming that the only practical way to get the duct back into the air filter case, once the duct is installed in the bike, is to PULL it from the outside, with the air filter removed. Because I certainly have no chance of getting any leverage on that duct, to be able to PUSH it into the back of the case. Heck, there's not even enough space for my hand.

By the way, the ear shave mod is definitely in my near future. Heck, it might even have to be today.

OK, so I put my bike back together after the battery fiasco, and wanted to take it for a test ride and make sure everything seemed fine. But I tried and tried to get those air filter bolts out, to no avail. I tried for a long time. I even considered cutting them off with an angle iron, which of course meant that I would likely damage the case and have to buy a new one, but desperation had sort of set it. I was also concerned that the angle grinder would catch the air filter on fire, or at least melt it. So I didn't consider that for very long.

So I have to be able to ride the bike, right? (first lie) And I'm responsible, right? (second lie, I guess) so I'm not going to run the bike without an air filter. That would be crazy.

So the obvious solution: Wad the foam air filter SCREEN (which can pop right off the bolts) into a ball and cram it into the hole where the duct goes. It will sit there and filter the air (maybe a little too much... one can't be sure). Maybe it will pop out while I'm riding (and heck, maybe it did), which of course negates the whole "won't run without an air filter" thing. Maybe it will get sucked into the intake and go into lord-knows-where (though I think I know -- the carb).

"But it will probably be fine, at least for a short test drive," I told myself.

So, I did take a ride. It wasn't long, but it wasn't just around the block at 20 mph either. I got up to speed and was out for 30 minutes or so. I even forgot that I had this "workaround" in place.

Fast forward to today. I got up early for a nice morning ride. I'm looking around the bike and I see the missing ear. "Oh yeah," I thought. "That."

So I check to make sure the balled-up air filter is still there, and it's GONE.

OK, I'm not a complete idiot (yeah, okay -- that's debatable at the moment). Clearly I'm not going for a ride this morning, and probably not until I get a new air filter screen, and perhaps an entire new air filter case and filter (or just do the ear shave and buy whatever filter I need for that).

But, of course, my situation could be much worse. What is the likelihood that the air filter was EXPELLED from the opening, and just ended up on the street. That's bad, because I ran the bike without anything in there at all, but it was a short time and it's probably not that big a deal.

A more likely scenario is that the screen was sucked INTO the intake (since that's the whole point of the intake), and one of two things happened: First, there's something in there that the screen is just resting against, because it's too big to be sucked in. So it's still doing what I asked of it (even though it was a stupid thing to ask), just in a harder-to-get-to place.

Then there's the scenario that concerns me more, which is that the screen got sucked directly into one of the carbs, at which point I'm not sure what may have happened. But it seems likely that it's just sitting there in the carb, not able to be broken down and "digested," but not able to be removed either. And it's just going to make the performance of that carb worse and could even damage the carb (and may have already).

A less likely scenario is that the air filter has not only disappeared, but it has been fully and completely digested by the bike, and has already left (in some form) via the exhaust pipe. I don't think it's likely, but it is a bad-ass thing to imagine -- that the Beast just chewed right through it without a thought.

I will say this: I took off last night when a light turned green. I wasn't hot dogging it, but I was "being a motorcycle" and getting gone at a decent clip. And as I cranked through the gears, I heard this sound and felt this sensation that I haven't experienced before. It's hard to describe, but if you told me it was the sound and feeling of an air filter screen going being chewed up by a carb and expelled by the exhaust system, I wouldn't say it was inconsistent with that. It was a sound and feeling that concerned me momentarily, but it was over as soon as it started, and everything else about the ride was inconsequential.

I think I know the answer, but I don't like it. You guys can help me confirm it:

I had already assumed I would be taking my carbs apart this weekend, when I couldn't figure out why the bike wouldn't start (before I realized this new AGM battery was failing). Once I replaced the battery, I breathed a sigh of relief that I wouldn't have to get into the carbs.

However, given that I did this stupid thing, if there's a decent chance that it got sucked in somewhere it's not supposed to be, and that it's still there, then I need to inspect until I find it. Starting with the big plastic air intake (which I understand may require removing the engine?), and if I don't find it there, then pulling the carbs and taking them apart to look for the screen, assess damage, or both.

Or maybe I'm overreacting, and the screen was OBVIOUSLY expelled out during the ride at some point, or it was OBVIOUSLY sucked in and consumed readily by The Beast, and I'll never see or hear from it again.

In any case, riding the bike right now sounds like a bad idea, because I don't know where that screen is (and that screen isn't, by itself, adequate filtration anyway).

I hope you will take into consideration my honesty as you consider what chastisement I deserve. I throw myself upon the mercy of the forum, and hereby nominate myself for the Hall of Shame, in the Impatience category.
 

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But here's the beginning of my problem: Once when I was taking off that right ear, I thought I needed to remove the bolts that secure the air filter, so I did (that's another reason to read up on these things before, instead of guessing). When I put those bolts back in, I must have done it wrong (too tight into the plastic or whatever), because now those bolts won't come out. And the fact that they won't come out prevents me from being able to remove the air filter from the air filter case.

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Over Tightening the air filter bolts isn't uncommon. What ends up happening is that the nut that's inside the plastic post starts turning inside because it's over tightened. This happened on one of my project bikes and I was able to get in behind the opening and put a vice grip on the inside of the filter box to hold that nut and get the bolts out. You can see what I mean on this pic. Click here
 

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I'd say the 'screen' probably just fell out. It's not a straight shot through the carb. First obstruction is the slide and needle, second is the butterfly. So if it's not hung up in the first 2-3" of the carb throat (should be able to touch it), it most likely fell out.

If caught under the slide, and around the needle, the engine would probably start flooding out on that cylinder due to air restriction and the slide being propped up.
 

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Discussion Starter #4
Over Tightening the air filter bolts isn't uncommon. What ends up happening is that the nut that's inside the plastic post starts turning inside because it's over tightened. This happened on one of my project bikes and I was able to get in behind the opening and put a vice grip on the inside of the filter box to hold that nut and get the bolts out.
Good advice. Thanks. I just gave it a shot, and I wasn't able to make any progress. I assume your vice grip was applying pressure to the outside of the top of the post, which is where that nut is. It can't make direct contact, with the nut, right?

I wasn't using vice grips, but I did use my go-to wrench. I didn't get the grip on the nut that I need, but I also wasn't completely sure that I was doing it right. I have to vice grips around here somewhere. I'll see if I can find them.
 

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You can use a green scrubbing pad with a little oil on it over the intake for a filter and it would be fine until you get something better. Unless you are groven down dirt roads or in the rain you would be fine.
 

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Discussion Starter #7
You can use a green scrubbing pad with a little oil on it over the intake for a filter and it would be fine until you get something better. Unless you are groven down dirt roads or in the rain you would be fine.
Thanks for that. I was hoping somebody might say something like "don't worry too much about the air filter, if you're just piddling around town for an hour." I want to get this fixed soon, but I'm not riding the bike AT ALL for now, because the last thing I want is to screw up my engine and have you guys say, "What? You ran without one of your air filters? You idiot!"

Don't get me wrong. I'm sure there's somebody who would say that exact thing :)
 

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Discussion Starter #8
Sounds like a perfect excuse to do a full earshsve. ;)
Yeah, I thought so too. Then I saw how much work is involved. I'm feeling a little lazy for that at the moment. In a perfect world, I'll buy the stuff I need for the ear shave in advance, and then have the stuff waiting for the perfect rainy weekend when I have nothing else to do.
 

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Yeah, I thought so too. Then I saw how much work is involved. I'm feeling a little lazy for that at the moment. In a perfect world, I'll buy the stuff I need for the ear shave in advance, and then have the stuff waiting for the perfect rainy weekend when I have nothing else to do.
Earshave was the first thing I did. Just buy some K&N filters, a crankcase filter, and some new jets. Fiddling with the carbs isn't hard (getting them back on is). Carbs willing, you can knock this out in an hour or so
 

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You might not even need new jets. Seriously it's an easy job. The only hard part is if you want to remove the center airbox under the tank in one piece. Most folks just cut it out.
The great thing about doing an earshave it makes removing the carbs A LOT easier than it was before. (Still not the most fun job on this bike)

Am guessing someone has the part numbers for the pod filters that fit along with a link ???
 

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Discussion Starter #11
You might not even need new jets. Seriously it's an easy job. The only hard part is if you want to remove the center airbox under the tank in one piece. Most folks just cut it out.
Oh, so that airbox will be removed? Yeah, that sounds like a good idea.
 

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Oh, so that airbox will be removed? Yeah, that sounds like a good idea.
Yeah, cut that B---- out man. You slap the air filters right on to the carbs. My filters seemed to be slightly too tall and the tank bent it down on the one side, but you wouldn't even know it by looking at it. Make the jump. We're here if you have questions
 

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Am guessing someone has the part numbers for the pod filters that fit along with a link ???
For Readparse:
These are what you need though you may find them cheaper elsewhere:

1 ea
Imgo crankcase filter:

https://www.amazon.com/gp/product/B0022ZZHG8/ref=oh_aui_bia_detailpage_o08_s00?ie=UTF8&psc=1

These are the K&Ns. You need two, of course. They've really gone up in the last few years, but there is another foam pod filter that some folks are using that are a lot cheaper, however the K&Ns will last for years and they look cool. You'll have to add a quarter inch in washers and a longer bolt under the rear of the fuel tank in order to clear the left K&N filter.
I don't know about the foam pods.

https://www.amazon.com/gp/product/B00062YOKO/ref=oh_aui_bia_detailpage_o08_s01?ie=UTF8&psc=1

Some folks use a sawzall to remove the plastic air box. I don't recommend it. It's too wild and you risk scraping the top of your front head and making an ugly mark. I used an 'endless hacksaw', the handle on one end and one end of the blade sticking out wild. You pull it to cut.
You could also drill a few holes in a line to get started and make it quicker.
Spockster says you can remove it in one piece by removing the wiring harness and moving the thermostat housing.
I weighed all the parts that I removed in the earshave and it totaled fourteen pounds.
One of the rubber tubes which you will no longer need has a right angle bend and can be cut to length to replace the current crankcase tube that plugs into the air box. You can mount the imgo filter on the lower screw hole for the left ear and route the modified tube to it from the crankcase.
I recommend getting a pair of eleven inch needle nose pliers to disconnect and reconnect the various hoses.
Don't try to remove the hose clamps, you'll just deform them. Instead, grasp the hose firmly with the needle nose pliers just beyond the nipple and pull them off. Push 'em back on the same way.

PS: If you decide to cut the airbox, drive some tapered wooden shims between the top of the front cylinder and the bottom of the airbox to keep it stationary.
 

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Discussion Starter #14
Hey, guess what! I found the air filter screen. Spockster said it either fell out, or was in the first 2-3 inches of the carb throat, and that I should be able to touch it.

I know it's been several days, but I actually haven't ridden at all since Friday (pretty crazy, since I normally ride nearly every day). I had a bunch going on over the weekend and early this week.

Anyway, it turns out it was there, and I actually could touch it, as long as my finger reached up a little (I had tried to feel for it last weekend, but it didn't seem to be there then. I used a little mirror tonight to look around the corner of the intake and I saw it. To pull it back far enough that I could get it out, I used an interesting rig: One of my rubber mallets has a hook in the end of the handle. I unscrewed that hook out of the handle and lashed the straight part of the hook (which is pretty long) to my index finger, using some electric wire. Use what you've got, right?

Finally it was close enough that I could use my finger to coax it out.

I have tried and tried to get these bolts out of the air filter that has the stripped receiver nuts (or whatever you want to call them). shark88 said he had some luck with vice grips on those nuts (which are actually under some rubber or plastic or whatever, so you can't actually get to the nuts themselves). I can't find my vice grips, for some reason. But I was squeezing the holy hell out of the thing with a pretty good wrench and made no progress on those bolts at all.

So I'm still contemplating what to do about that, though I did ride the bike tonight, since I'm not going out riding in the dirt and I'm not riding in the rain. I could certainly cut the bolts off with an angle grinder, but then I would have to find a way to get their stubs out. I could buy a whole new air filter case, but that seems stupid.

Especially since everybody is telling me to do the ear shave. Yeah, I probably should, but I'll keep thinking about it.

I'm just glad I went for a ride tonight. Oh, and I had the POGS issue, but I couldn't remember what to do about it. So I decided to pull over and look it up on this site, and I remembered it's the carb vent hose. I checked my temporary workaround -- since that's the ear I'm missing. I had actually tucked the hose up under the tank and taped it to the tank with -- uh, electrical tape (sorry). That tape had come loose enough that I guess the hose was getting whipped around at speed, and my POGS was pretty bad.

So I taped it back up, made sure it was fully under the tank, to stay out of the breeze, and I was on my way. The POGS went away and I stayed out for a long time. Wonderful ride, great temperature, and I didn't want to stop. I love this bike.

Yeah, yeah... ear shave. I know :) Thanks guys.
 

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Discussion Starter #15
For Readparse:
These are what you need though you may find them cheaper elsewhere...
Thanks for the encouragement, roadpouring. Lots of good info here. I didn't see this comment until just now.
 

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Discussion Starter #16
Yeah, cut that B---- out man. You slap the air filters right on to the carbs. My filters seemed to be slightly too tall and the tank bent it down on the one side, but you wouldn't even know it by looking at it. Make the jump. We're here if you have questions
Ha! I like the way you think. You guys might convince me after all.
 

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Ha! I like the way you think. You guys might convince me after all.
Just do it. You obviously have the knowledge to do it. As for your POOGS issue, make sure it is POOGS. Go for a ride with the gas cap unlatched. POOGS is caused by a clogged vent in the gas cap. I'd think it might be because of your missing air filter. If you get some uneven wind fitting your air intake, it'll mess with it and cause the bike to lose power. Sometimes on the highway in the windy stretch of RT 15 in Maryland, I get a little rev dip from the wind blowing at me
 

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Discussion Starter #18
As for your POOGS issue, make sure it is POOGS. Go for a ride with the gas cap unlatched. POOGS is caused by a clogged vent in the gas cap.
I didn't have a problem once I re-taped the carb vent hose under the gas tank. Well actually, I opened and shut the gas cap also, just in case.

So you're saying that riding with the gas cap unlatched should work around the POOGS issue, right? I do keep meaning to take off my gas cap, disassemble, inspect, clean, etc. That sounds like a pretty easy job. Anyway, I'm glad it went away. The first part of that ride sucked. The POOGS was so bad I felt like it was gonna jerk me off the bike eventually. So then I pulled over, looked it up on this site on my phone, did a couple of things, and was fine.
 

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POOGS has nothing to do with the carb vent hose, that's a separate issue. Riding with the gas cap open would not have helped you.

The carb vent hose end must be in still air so it's at atmospheric pressure. Air moving past the end of the hose can raise or lower the air pressure in the carb, resulting in either fuel starvation or over rich conditions.
Google "how an atomizer works"

POOGS occours when the tank is about half empty and the gas cap isn't replacing the loss of fuel as the bike runs with incoming air. This creates a vacuum in the tank and fuel slows or stops flowing.
Take a full bottle of water with the cap screwed on tight an punch a tiny hole in the bottom with an ice pick. A few drops of water may run out but it will stop flowing. Now unscrew the cap. The water will now run out in a stream.
Same concept with the fuel in the tank. ;)
 

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@readparse

I wouldn't rely on tape to secure the vent tube. It'll let you down again at some point.

The vent tube naturally points forward to the front of the bike.
Bend the tube backwards in a U-shape so that it's pointing towards the rear of the bike and then zip tie it(without collapsing it) to the wiring harness and just behind the thermostat housing.

Some plug the vent tube into a plastic nipple underneath the tank.
I don't do that since I don't like wrestling with the vent tube when removing and reinstalling the tank... especially when it's full of fuel.
 
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